Recovery method and device for normal-pressure rectification and purification of waste methanol

Abstract

The invention relates to the technical field of waste methanol purification, in particular to a recovery method and device for normal-pressure rectification and purification of waste methanol, the device comprises a reaction kettle, a condenser, a reflux tank, a standing tank and a filtering tank, one end of the reflux tank is connected with a rectification column tower, the other end of the reflux tank is connected with a storage tank, and the side edge of the reaction kettle is connected with a transfer tank. The bottom of the reaction kettle is connected with a discharge treatment tank; the method further comprises the following steps: S1, filtering; s2, standing is carried out; s3, feeding the materials; s4, heating is conducted; s5, separating; s6, performing reflux; s7, detecting; and S8, cleaning. When corresponding waste methanol is generated in a workshop, the waste methanol can be recycled, purified and reused, pretreatment impurity removal, material supply, heat supply, stirring and auxiliary evaporation are performed through corresponding technological processes, and then corresponding rectification, condensation and purification are performed, so that the liquid methanol with corresponding purity is obtained, a certain economic benefit is created, the production cost is saved, and the economic benefit is increased. And environmental pollution can be prevented, and the purpose of environmental protection is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of waste methanol purification, and specifically provides a recovery method and device for purifying waste methanol by atmospheric distillation. Background Art

[0002] Methanol is an important basic chemical raw material and an excellent solvent, with wide applications. Since methanol is miscible with water and miscible with a variety of organic solvents, a large amount of waste methanol is generated during production, preparation, and use. The main sources of generation are processes such as cleaning, decontamination, dilution, and extraction in industrial production. For example, the waste methanol generated in workshops such as trihydroxy and insulating resin mainly contains water, methanol, and a small amount of organic impurities. Due to the flammable, corrosive, volatile, or reactive properties of methanol, it is listed in the hazardous waste list. However, a large amount of useful components are contained in waste methanol. Through recovery and treatment, it can be extracted, purified, and reused to achieve resource reuse. As a by-product, selling it directly has a relatively low price. Moreover, if these waste methanol are not recycled, it will cause resource waste and environmental pollution;

[0003] In this regard, Chinese Patent Application No.: 201810806922.X discloses a rectification adsorption purification process for waste methanol, belonging to the technical field of material purification and recovery. It is characterized in that the high-NH3 waste methanol generated in the methanol circulation process of low-temperature methanol washing enters a preheater for preheating. The high-NH3 waste methanol is rectified and separated in a rectification tower. A mixture of NH3, H2S, and methanol is obtained from the top of the rectification tower, and low-NH3 methanol is obtained at the bottom of the rectification tower. The mixture is cooled by a condenser and then enters a buffer tank. The gas phase enters an adsorption reactor to remove hydrogen sulfide therein. The high-ammonia methanol coming out of the buffer tank and the high-ammonia methanol coming out of the adsorption reactor are mixed and output as waste methanol from the waste methanol discharge pipe;

[0004] However, the existing purification devices are inconvenient for pretreatment, auxiliary feeding, heating evaporation, and condensation recovery according to the purification requirements of the waste methanol generated in workshops such as trihydroxy and insulating resin in this company, which affects the operation efficiency and effect;

[0005] Therefore, in order to solve the above problems, a recovery method and device for purifying waste methanol by atmospheric distillation are proposed. Summary of the Invention

[0006] The purpose of the present invention is to provide a recovery method and device for purifying waste methanol by atmospheric distillation, so as to solve the problem that the existing purification devices are inconvenient for pretreatment, auxiliary feeding, heating evaporation, and condensation recovery according to the purification requirements of the waste methanol generated in workshops such as trihydroxy and insulating resin in this company, which affects the operation efficiency and effect.

[0007] To achieve the above object, the present invention provides the following technical scheme: a method and device for recovering waste methanol by atmospheric distillation purification, comprising a reactor, a distillation column tower is connected above the reactor, a condenser is connected above the distillation column tower, a reflux tank is connected below the condenser, one end of the reflux tank is connected to the distillation column tower, and the other end of the reflux tank is connected to a storage tank, a transfer tank is connected to the side of the reactor, a standing tank is connected to the side of the transfer tank, and a filter tank is connected to the side of the standing tank, and a discharge treatment tank is connected to the bottom of the reactor;

[0008] The following steps are also included:

[0009] S1. Filtration: During pretreatment, the waste methanol solution is introduced into a filter tank to filter and remove solid impurities in the waste methanol;

[0010] S2, standing: During pretreatment, the waste methanol filtered in S1 is transferred to a standing tank and allowed to stand for a period of time to allow the water and some organic impurities with higher density in the waste methanol to settle naturally and separate from the methanol phase. The water and impurities in the lower layer are then discharged through the discharge port at the bottom of the standing tank, and the waste methanol is discharged into the transfer tank through the side of the standing tank;

[0011] S3, feeding: transporting the pretreated waste methanol to a reactor connected to a distillation column, and adding a corresponding liquid alkali solution and stirring;

[0012] S4, heating: hot steam is introduced into the steam pipe inside the reactor to heat the inside of the reactor, and the temperature is slowly raised to 70-80°C;

[0013] S5, separation: the methanol that has reached the boiling point and evaporated enters the distillation column tower through the top of the reactor in turn;

[0014] S6, reflux: after the reaction begins to reflux, the washing distillation system is refluxed for half an hour and the reflux ratio is set to collect methanol and heavy components in batches, that is, the methanol condensed by the condenser is refluxed into the reflux tank, and then refluxed to the top of the distillation column and the extracted part is stored in the storage tank;

[0015] S7. Testing: Use relevant testing equipment to test the acidity, moisture, gas phase and other indicators of each batch of methanol after purification and distillation;

[0016] S8, cleaning: the waste liquid at the bottom of the reactor is treated and discharged into the discharge treatment tank for subsequent treatment and cleaning of related equipment.

[0017] As a further step of this solution, specifically, the outside of the rectification column tower is wrapped and equipped with an electric heating component, and a thermometer is inserted and assembled on the outer wall of the rectification column tower. A corresponding condensing medium circulation and conveying component is assembled and connected to the side of the condenser, and the electric heating component, the thermometer, and the condensing medium circulation and conveying component are connected to a corresponding power distribution control module for power supply control.

[0018] As a further step of this solution, specifically, a reflux pump and a withdrawal pump are respectively connected and assembled at both ends of the reflux tank. The output end of the reflux pump is connected to the upper side reflux port of the rectification column tower, and the output end of the withdrawal pump is connected to the liquid inlet of the storage tank. A flow control valve I is assembled between the reflux tank and the reflux pump, and a flow control valve II is assembled between the reflux tank and the withdrawal pump.

[0019] As a further step of this solution, specifically, a liquid inlet pipe and a feed pipe are respectively fixed on the upper left and right sides of the reactor. A corresponding feed pump is assembled between the liquid inlet pipe and the transfer tank, and the feed pipe is docked with a corresponding alkali solution supply device. A corresponding steam heating pipe is assembled inside the reactor, and a corresponding steam medium circulation and conveying component is connected to the side of the reactor. A corresponding pressure transmitter, temperature sensor, and corresponding docking port, etc. are assembled on the top cover of the reactor. A bottom bin is assembled at the bottom of the reactor. A solenoid valve is assembled at the drain outlet of the bottom bin, and the solenoid valve is connected to a discharge treatment tank through a discharge pipe.

[0020] As a further step of this solution, a stirring component and a scraping component are also assembled inside the reactor. The stirring component is arranged inside the steam heating pipe in a surrounding manner, and the scraping component is arranged inside and outside the steam heating pipe in a surrounding manner. A driving component corresponding to the stirring component and the scraping component is assembled on the top of the reactor. The driving component includes a gear box supported on the surface of the reactor top cover. An inner shaft and a rotating cylinder are inserted and assembled inside the gear box through bearings, and the inner shaft is inserted and assembled inside the rotating cylinder through a bearing. The top of the inner shaft is connected to a reducer through a coupling, and the output end of the reducer is connected to a motor. The reducer and the motor are both supported and assembled above the gear box. The inner shaft and the rotating cylinder are inserted and assembled through bearings in the center of the reactor top cover and extend into the reactor.

[0021] As a further step of this solution, the steam heating pipe is arranged in a spiral surrounding shape. The left and right ends of the steam heating pipe are respectively integrally fixed with a steam inlet pipe and a steam outlet pipe, and the steam inlet pipe and the steam outlet pipe are inserted and assembled on the left and right side walls of the upper part of the reactor through a sealing flange.

[0022] As a further aspect of this solution, the stirring assembly includes an inner stirring rod and an outer stirring rod that are vertically parallel to each other. The upper ends of the inner stirring rod and the outer stirring rod are horizontally and fixedly provided with an upper beam, and the middle part of the upper beam is assembled on the lower part of the outer wall of the rotating cylinder. The scraping assembly includes an inner scraping rod, a middle scraping rod, and an outer scraping rod that are vertically parallel to each other. The upper end of the inner scraping rod is supported and assembled on the outer wall of the lower end of the inner shaft. The bottom ends of the inner scraping rod, the middle scraping rod, and the outer scraping rod are horizontally and fixedly provided with a lower beam. The outer side of the outer scraping rod is attached to the inner wall of the reaction kettle. The steam heating pipe is spirally wound between the outer scraping rod and the outer stirring rod, and the upper end of the outer scraping rod is lower than the bottom walls of the steam inlet pipe and the steam outlet pipe. The middle scraping rod is located between the inner stirring rod and the outer stirring rod, and the inner scraping rod is located inside the inner stirring rod.

[0023] As a further aspect of this solution, the upper end of the middle scraping rod is horizontally and fixedly provided with an upper ring, and the upper ring is lower than the upper beam. The lower ends of the inner stirring rod and the outer stirring rod are both fixedly provided with corresponding lower rings, and the lower rings are higher than the lower beam. The lower end of the outer scraping rod is fixedly provided with a corresponding scraping bottom rod, and the scraping bottom rod is arc-shaped. The surface of the scraping bottom rod is supported by support ribs, and the upper ends of the support ribs are fixedly supported on the lower beam.

[0024] As a further aspect of this solution, corresponding upper bevel gears, side bevel gears, and lower bevel gears are arranged inside the gearbox. The side bevel gear meshes below the side of the upper bevel gear. The upper side of the lower bevel gear meshes with the lower side of the side bevel gear. The side bevel gear is assembled on the side wall of the gearbox through a shaft and bearings. The upper bevel gear is fixed to the upper end of the inner shaft, and the side bevel gear is fixed to the outer wall of the upper end of the rotating cylinder.

[0025] As a further aspect of this solution, the reaction kettle is arranged in a four-equal-part form. Sealing gaskets are filled between the adjacent sides of the four equal parts of the reaction kettle and are assembled by inserting bolts. The side bottoms of the reaction kettle and the bottom bin are supported by a support frame. The outer wall of the reaction kettle is wrapped with heat-insulating cotton. An arm is supported outside the heat-insulating cotton, and the arm is assembled on the outer side wall of the reaction kettle through bolts.

[0026] Compared with the prior art, the beneficial effects of the present invention are:

[0027] 1. Through the setting of corresponding technological processes and the connection of devices, when waste methanol is generated in the workshop, it can be recovered, purified, and reused, which not only creates certain economic benefits, saves production costs, but also prevents environmental pollution and achieves the purpose of environmental protection;

[0028] 2. By setting up a filtration tank, a settling tank and a transfer tank, it is convenient to conduct corresponding pre-filtration before purifying waste methanol, such as a bag filter or a cartridge filter, to remove solid impurities in the waste methanol, such as metal chips, dust, etc., to prevent them from entering subsequent equipment, affecting the rectification effect or damaging the equipment. At the same time, after standing for a period of time, the water and some organic impurities with a relatively large density in the waste methanol will naturally settle and separate from the methanol. Subsequently, it is transferred through the transfer tank for subsequent feeding into the reaction kettle. Through this design, pre-filtration is convenient and beneficial to subsequent rectification and purification;

[0029] 3. By setting up a reaction kettle, after feeding by a feed pump and adding corresponding lye for stirring, such as adding sodium hydroxide solution, etc., it is convenient to promote impurity separation, adjust the pH value and assist rectification. Utilizing the principles of acid-base neutralization, azeotrope destruction and boiling point difference, it is convenient for subsequent purification of waste methanol. Subsequently, it is heated to a corresponding temperature through a steam heating pipe and a steam medium circulation and transportation component. By driving the stirring of the stirring component and the scraping component by a driving component, the rectification operation becomes more convenient and efficient. Through this design, it is convenient to assist the reaction and evaporation supply to the rectification column for rectification, making the subsequent operation more convenient;

[0030] 4. While the above structural design is carried out, after rectification by the rectification column, it is condensed and liquefied in the condenser. Subsequently, the liquid methanol is distributed for reflux and extraction through the reflux tank for reflux and storage. Further, waste liquid is discharged and relevant products are detected and cleaned, making the operation safer and more hygienic and convenient for subsequent use. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0032] Figure 1 It is a schematic process flow diagram of the present invention;

[0033] Figure 2 It is a schematic connection and assembly diagram of the process device of the present invention;

[0034] Figure 3 It is a front view schematic diagram of the partial structure of the rectification column of the present invention;

[0035] Figure 4 It is a front view schematic diagram of the partial structure of the reflux tank of the present invention;

[0036] Figure 5 It is a front view three-dimensional schematic diagram of the partial structure of the reaction kettle of the present invention;

[0037] Figure 6 This is the front view sectional three-dimensional schematic diagram of the local structure of the reactor of the present invention;

[0038] Figure 7 This is the top view sectional three-dimensional schematic diagram of the local structure of the reactor of the present invention;

[0039] Figure 8 This is the side view three-dimensional schematic diagram of the internal structure of the reactor of the present invention.

[0040] In the figure: 100, reactor; 101, liquid inlet pipe; 102, feed pipe; 103, bottom bin; 104, support frame; 105, thermal insulation cotton; 106, holding arm; 110, rectification column tower; 111, electric heating component; 112, thermometer; 120, condenser; 121, condensate medium circulation and transportation component; 130, transfer tank; 131, feed pump; 140, static tank; 150, filter tank; 160, reflux tank; 161, reflux pump; 162, product withdrawal pump; 163, flow control valve I; 164, flow control valve II; 170, storage tank; 180, discharge treatment tank; 181, solenoid valve; 182, discharge pipe; 200, steam heating pipe; 201, steam medium circulation and transportation component; 210, steam inlet pipe; 220, steam outlet pipe; 300, stirring component; 301, upper beam; 310, inner stirring rod; 311, lower ring; 320, outer stirring rod; 400, scraping component; 401, lower beam; 410, inner scraping rod; 420, middle scraping rod; 421, upper ring; 430, outer scraping rod; 440, bottom scraping rod; 441, support rib; 500, driving component; 501, inner shaft; 502, rotating cylinder; 510, gearbox; 511, upper bevel gear; 512, side bevel gear; 513, lower bevel gear; 520, reducer; 530, motor. Detailed implementation manners

[0041] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0042] Please refer to Figures 1-8, an embodiment provided by the present invention: a method and device for recovering waste methanol by atmospheric distillation and purification, including a reaction kettle 100, a rectifying column tower 110 is connected above the reaction kettle 100, a condenser 120 is connected above the rectifying column tower 110, a reflux tank 160 is connected below the condenser 120, one end of the reflux tank 160 is connected to the rectifying column tower 110, and the other end of the reflux tank 160 is connected to a storage tank 170. A transfer tank 130 is connected to the side of the reaction kettle 100, a static tank 140 is connected to the side of the transfer tank 130, and a filter tank 150 is connected to the side of the static tank 140. A discharge treatment tank 180 is connected to the bottom of the reaction kettle 100;

[0043] It also includes the following steps:

[0044] S1. Filtration: During pretreatment, the waste methanol solution is introduced into the filter tank 150, and the solid impurities in the waste methanol are first filtered out, that is, the solid slag foreign matter impurities in the waste are first removed through the corresponding filter components, which is convenient for pretreatment of the waste methanol generated in the company's trihydroxy, insulating resin and other workshops, and it mainly contains water, methanol and a small amount of organic impurities;

[0045] S2. Static settlement: During pretreatment, the waste methanol filtered in S1 is transferred to the static tank 140 and left to stand for a period of time, so that the water and some organic impurities with a larger density in the waste methanol naturally settle and separate from methanol. Then, the lower-layer water and impurities are discharged through the discharge port at the bottom of the static tank 140, and the pretreated waste methanol is discharged to the inside of the transfer tank 130 through the side of the static tank 140, so as to transfer and store the pretreated waste methanol inside the transfer tank 130 for subsequent use and pumping;

[0046] S3. Feeding: The pretreated waste methanol is transported to the reaction kettle 100 connected to the rectifying column tower 110, and at the same time, the corresponding liquid alkali solution is added and stirred, so as to facilitate the separation of impurities, adjustment of pH value and auxiliary rectification through the principles of acid-base neutralization, azeotrope destruction and boiling point difference;

[0047] S4. Heating: Hot steam is introduced into the steam pipeline inside the reaction kettle 100 to heat the inside of the reaction kettle 100, and the temperature is slowly raised to 70-80 °C. The corresponding heat is circulated and supplied to the inside of the steam heating pipe 200 through the corresponding steam medium circulation and delivery component 201 for heating, so as to reach the boiling point required for methanol evaporation;

[0048] S5. Separation: The methanol that reaches the boiling point and evaporates enters the interior of the rectifying column 110 successively from the top of the reaction kettle 100, and is rectified and stripped through the corresponding structure inside the rectifying column 110. That is, after the steam enters from the bottom of the rectifying column 110, when the rising gas phase contacts the descending liquid phase, due to the temperature difference and concentration difference, a mass transfer and heat transfer process will occur. The high-boiling components in the gas phase, such as water and organic impurities, will partially condense and enter the liquid phase, while the low-boiling component methanol in the liquid phase will partially vaporize and enter the gas phase. This process continues, making the concentration of methanol in the gas phase gradually increase. Subsequently, by utilizing the difference in volatility of each component, the methanol in the liquid phase is vaporized and rises as much as possible by heating. In the stripping section, the rising steam and the descending liquid phase carry out mass transfer and heat transfer, enabling the methanol in the liquid phase to continuously vaporize and enter the gas phase, thereby increasing the recovery rate of methanol;

[0049] S6. Reflux: Wait until there is a reflux phenomenon at the start of the reaction. After refluxing and washing the rectifying system for half an hour, start setting the reflux ratio to batch-collect methanol and heavy components. That is, the methanol condensed by the condenser 120 flows back into the reflux tank 160, and then is respectively refluxed to the upper part of the rectifying column 110 and part is taken out and stored inside the storage tank 170. That is, the cold liquid methanol condensed by the condenser 120 flows back to the top of the rectifying column 110, providing a stable liquid-phase reflux for the rectifying column 110, thereby maintaining the gas-liquid balance and stable separation effect inside the rectifying column 110; The reflux liquid serves as the descending liquid phase and fully carries out mass transfer and heat transfer with the rising gas phase in the rectifying section, enabling the rectifying process to continue effectively;

[0050] S7. Detection: Use relevant detection equipment to detect indicators such as acidity, moisture, and gas phase of each batch of methanol after purification and rectification, conduct detection and analysis on the above-mentioned extracted products, and use instruments such as gas chromatographs to detect indicators such as the purity, water content, and content of organic impurities of methanol to ensure that the product quality meets the standard requirements;

[0051] S8. Cleaning: Treat the waste liquid at the bottom of the reaction kettle 100 and discharge it into the discharge treatment tank 180 for subsequent treatment and clean the relevant equipment; The residual liquid contains water and a small amount of organic impurities that have not been completely separated. According to the nature and composition of the residual liquid, adopt appropriate methods for treatment. If the organic impurities in the residual liquid have recycling value, other separation methods can be further used for recycling; If the residual liquid has no recycling value, it needs to be transported to the sewage treatment system for treatment and discharged after meeting the environmental protection discharge standards.

[0052] More specifically, in this embodiment, an electric heating component 111 is wrapped around the outside of the rectification column tower 110, and a thermometer 112 is inserted and assembled on the outer wall of the rectification column tower 110. A corresponding condensing medium circulation and conveying component 121 is assembled and connected to the side of the condenser 120. The electric heating component 111, the thermometer 112, and the condensing medium circulation and conveying component 121 are connected to a corresponding power distribution control module for power supply control. In this way, it is convenient to control the temperature heating of the rectification column tower 110. Through the corresponding power distribution control module, it is determined whether to heat according to the digital display of the thermometer 112 to ensure the corresponding rectification temperature. At the same time, with the cooperation of the condensing medium circulation and conveying component 121, it is convenient to supply the corresponding cooling medium to the inside of the condenser 120 to ensure the condensing effect;

[0053] More specifically, in this embodiment, a reflux pump 161 and a withdrawal pump 162 are respectively connected and assembled at both ends of the reflux drum 160. The output end of the reflux pump 161 is connected to the reflux port on the upper side of the rectification column tower 110, and the output end of the withdrawal pump 162 is connected to the liquid inlet of the storage tank 170. A flow control valve 163 is assembled between the reflux drum 160 and the reflux pump 161, and a flow control valve 164 is assembled between the reflux drum 160 and the withdrawal pump 162. In this way, during operation, it is convenient to transfer and distribute the condensed cold liquid methanol for reflux and withdrawal in corresponding proportions. The cooperation of the reflux pump 161 and the flow control valve 163, as well as the cooperation of the withdrawal pump 162 and the flow control valve 164, are used for corresponding control, making the operation more convenient;

[0054] More specifically in this embodiment, on the left and right sides of the upper part of the reactor 100, a liquid inlet pipe 101 and a feed pipe 102 are respectively fixedly provided. A corresponding feed pump 131 is assembled between the liquid inlet pipe 101 and the transfer tank 130, and the feed pipe 102 is connected to a corresponding alkali solution supply device. A corresponding steam heating pipe 200 is assembled inside the reactor 100, and a corresponding steam medium circulation and transportation component 201 is connected to the side of the reactor 100. A corresponding pressure transmitter, temperature sensor and corresponding docking ports are assembled on the top cover of the reactor 100. A bottom bin 103 is assembled at the bottom of the reactor 100. A solenoid valve 181 is assembled at the drain outlet of the bottom bin 103, and the solenoid valve 181 is connected to a discharge treatment tank 180 through a discharge pipe 182. In this way, it is convenient to dock the reactor 100, and at the same time, it is also convenient to disassemble and clean the reactor 100. A stirring component 300 and a scraping component 400 are also assembled inside the reactor 100. The stirring component 300 surrounds the inner side of the steam heating pipe 200, and the scraping component 400 surrounds the inner and outer sides of the steam heating pipe 200. A driving component 500 corresponding to the stirring component 300 and the scraping component 400 is assembled on the top of the reactor 100. The driving component 500 includes a gear box 510 supported on the surface of the top cover of the reactor 100. An inner shaft 501 and a rotating cylinder 502 are inserted and assembled inside the gear box 510 through bearings, and the inner shaft 501 is inserted and assembled inside the rotating cylinder 502 through a bearing. The top of the inner shaft 501 is connected to a reducer 520 through a coupling, and the output end of the reducer 520 is connected to a motor 530. The reducer 520 and the motor 530 are both supported and assembled above the gear box 510. The inner shaft 501 and the rotating cylinder 502 are inserted and assembled through bearings at the center of the top cover of the reactor 100 and extend into the reactor 100. In this way, when heating the inside of the reactor 100 by the steam heating pipe 200, it is convenient to drive the stirring component 300 and the scraping component 400 to stir through the driving component 500, so that the mixing is more uniform and the temperature heating is also more uniform, which helps with good evaporation;

[0055] More specifically in this embodiment, the steam heating pipe 200 is arranged in a spiral winding shape. The left and right ends of the steam heating pipe 200 are integrally and fixedly provided with a steam inlet pipe 210 and a steam outlet pipe 220 respectively. The steam inlet pipe 210 and the steam outlet pipe 220 are inserted and assembled on the left and right side walls of the upper part of the reaction kettle 100 through sealing flanges. In this way, the docking is more convenient, and the full contact between the liquid and the heat transfer medium is increased, making the heating more convenient and fast. The stirring assembly 300 includes an inner stirring rod 310 and an outer stirring rod 320 that are vertically parallel to each other. The upper ends of the inner stirring rod 310 and the outer stirring rod 320 are horizontally and fixedly provided with an upper beam 301. The middle part of the upper beam 301 is assembled on the lower part of the outer wall of the rotating cylinder 502. The scraping assembly 400 includes an inner scraping rod 410, a middle scraping rod 420, and an outer scraping rod 430 that are vertically parallel to each other. The upper end of the inner scraping rod 410 is supported and assembled on the lower outer wall of the inner shaft 501. The bottom ends of the inner scraping rod 410, the middle scraping rod 420, and the outer scraping rod 430 are horizontally and fixedly provided with a lower beam 401. The outer side of the outer scraping rod 430 is attached to the inner wall of the reaction kettle 100. The steam heating pipe 200 is spirally wound between the outer scraping rod 430 and the outer stirring rod 320. The upper end of the outer scraping rod 430 is lower than the bottom walls of the steam inlet pipe 210 and the steam outlet pipe 220. The middle scraping rod 420 is located between the inner stirring rod 310 and the outer stirring rod 320, and the inner scraping rod 410 is located inside the inner stirring rod 310. In this way, it is convenient for the rotation of the steam heating pipe 200 and the stirring assembly 300 without interference, and it is also convenient for the circulating agitation around the steam heating pipe 200, making the solution mix evenly and the heating temperature uniform;

[0056] More specifically in this embodiment, the upper end of the middle scraping rod 420 is horizontally and fixedly provided with an upper ring 421, and the upper ring 421 is lower than the upper beam 301. The lower ends of the inner stirring rod 310 and the outer stirring rod 320 are both fixedly provided with corresponding lower rings 311, and the lower rings 311 are higher than the lower beam 401. The lower end of the outer scraping rod 430 is fixedly provided with a corresponding scraping bottom rod 440, and the scraping bottom rod 440 is arc-shaped. The surface of the scraping bottom rod 440 is supported by support ribs 441, and the upper ends of the support ribs 441 are fixedly supported with the lower beam 401. In this way, it is convenient for the stable support and rotation of the stirring assembly 300 and the scraping assembly 400. At the same time, it is also convenient for scraping the inner wall of the bottom bin 103 and the inside of the reaction kettle 100, so that the liquid is not easy to remain, facilitating subsequent operations and cleaning. Inside the gearbox 510, there are corresponding upper bevel gears 511, side bevel gears 512, and lower bevel gears 513. The side bevel gear 512 meshes below the side of the upper bevel gear 511. The upper side of the lower bevel gear 513 meshes with the lower side of the side bevel gear 512. The side bevel gear 512 is assembled on the side wall of the gearbox 510 through a shaft and bearings. The upper bevel gear 511 is fixed to the upper end of the inner shaft 501, and the side bevel gear 512 is fixed to the upper outer wall of the rotating cylinder 502. In this way, it is convenient for the transmission of the inner shaft 501 and the rotating cylinder 502, and it is also convenient for the concentric and synchronous forward and reverse rotation of the inner shaft 501 and the rotating cylinder 502, facilitating the forward and reverse rotation of the steam heating pipe 200 and the stirring assembly 300, making the stirring more convenient;

[0057] More specifically in this embodiment, the reaction kettle 100 is arranged in four equally divided parts, and sealing gaskets are filled in the adjacent sides of the four equally divided parts of the reaction kettle 100 and assembled by inserting bolts. The reaction kettle 100 and the bottom bin 103 are supported by a support frame 104 at the bottom of the side. The outer wall of the reaction kettle 100 is wrapped with a heat-insulating cotton 105, and an arm 106 is supported outside the heat-insulating cotton 105. The arm 106 is assembled on the outer side wall of the reaction kettle 100 by bolts. In this way, it is convenient to disassemble, clean, assemble and maintain the reaction kettle 100, making it safer to use, not easy to cause scalding, etc., and facilitating safe use and operation.

[0058] The above is only a preferred embodiment of the present invention, and it is not intended to limit the present invention in any form; any ordinary technical personnel in the industry can smoothly implement the present invention as shown in the accompanying drawings of the specification and the above; however, any slight changes, modifications and equivalent changes made by those skilled in the art within the scope of the technical solution of the present invention by using the technical content disclosed above are all equivalent embodiments of the present invention; at the same time, any equivalent changes, modifications and evolutions made to the above embodiments based on the essence of the present invention still fall within the protection scope of the technical solution of the present invention.

Claims

1. A method and device for recovering waste methanol purified by atmospheric distillation, comprising a reactor (100), wherein a distillation column (110) is connected above the reactor (100), a condenser (120) is connected above the distillation column (110), a reflux tank (160) is connected below the condenser (120), one end of the reflux tank (160) is connected to the distillation column (110), and the other end of the reflux tank (160) is connected to a storage tank (170), a transfer tank (130) is connected to the side of the reactor (100), a stationary tank (140) is connected to the side of the transfer tank (130), and a filter tank (150) is connected to the side of the stationary tank (140), and a discharge treatment tank (180) is connected to the bottom of the reactor (100); Features: The following steps are also included: S1, filtration: during pretreatment, the waste methanol solution is introduced into a filter tank (150) and first filtered to remove solid impurities in the waste methanol; S2, standing: during pretreatment, the waste methanol filtered in S1 is transferred to a standing tank (140) and allowed to stand for a period of time to allow the water and some organic impurities with higher density in the waste methanol to settle naturally and separate from the methanol phase, and then the water and impurities in the lower layer are discharged through the discharge port at the bottom of the standing tank (140), and the waste methanol is discharged into the transfer tank (130) through the side of the standing tank (140); S3, feeding: transporting the pretreated waste methanol to a reaction kettle (100) connected to a distillation column (110), and adding a corresponding liquid alkali solution and stirring; S4, heating: hot steam is introduced into the steam pipe inside the reactor (100) to heat the inside of the reactor, and the temperature is slowly raised to 70-80° C.; S5, separation: the methanol that has reached the boiling point and evaporated enters the interior of the distillation column (110) through the top of the reaction kettle (100); S6, reflux: after the reaction begins to reflux, the reflux washing distillation system is refluxed for half an hour and the reflux ratio is set to collect methanol and heavy components in batches, that is, the methanol condensed by the condenser (120) is refluxed into the reflux tank (160), and then refluxed to the top of the distillation column (110) and the extracted part is stored in the storage tank (170); S7. Testing: Use relevant testing equipment to test the acidity, moisture, gas phase and other indicators of each batch of methanol after purification and distillation; S8, cleaning: the waste liquid at the bottom of the reactor (100) is treated and discharged into the discharge treatment tank (180) for subsequent treatment and cleaning of related equipment.

2. The method and device for recovering waste methanol by atmospheric distillation purification according to claim 1, characterized in that: Specifically, the distillation column (110) is externally wrapped with an electric heating component (111), and a thermometer (112) is inserted into the outer wall of the distillation column (110). The side of the condenser (120) is connected with a corresponding condensing medium circulation and conveying component (121), and the electric heating component (111), the thermometer (112) and the condensing medium circulation and conveying component (121) are connected to a corresponding power distribution control module for power supply control.

3. The method and device for recovering waste methanol by atmospheric distillation purification according to claim 1, characterized in that: Specifically, the two side ends of the reflux tank (160) are respectively connected to a reflux pump (161) and a production pump (162), and the output end of the reflux pump (161) is connected to the reflux port on the upper side of the distillation column (110), and the output end of the production pump (162) is connected to the liquid inlet of the storage tank (170). A flow control valve 1 (163) is installed between the reflux tank (160) and the reflux pump (161), and a flow control valve 2 (164) is installed between the reflux tank (160) and the production pump (162).

4. The method and device for recovering waste methanol by atmospheric distillation purification according to claim 1, characterized in that: Specifically, a liquid inlet pipe (101) and a feed pipe (102) are respectively fixed on the left and right sides of the upper part of the reactor (100); a corresponding feed pump (131) is installed between the liquid inlet pipe (101) and the transfer tank (130); and the feed pipe (102) is connected to a corresponding alkaline solution supply device; a corresponding steam heating pipe (200) is installed inside the reactor (100); and a corresponding steam medium circulation and conveying component (201) is connected to the side of the reactor (100); a corresponding pressure transmitter, a temperature sensor and a corresponding docking port are installed on the top cover of the reactor (100); a bottom bin (103) is installed at the bottom of the reactor (100); a solenoid valve (181) is installed at the bottom discharge port of the bottom bin (103); and the solenoid valve (181) is connected to the discharge treatment tank (180) through a discharge pipe (182).

5. A method and device for recovering waste methanol by atmospheric distillation purification according to claim 4, characterized in that: The reactor (100) is further provided with a stirring assembly (300) and a stirring and scraping assembly (400), wherein the stirring assembly (300) surrounds the inner side of the steam heating pipe (200), and the stirring and scraping assembly (400) surrounds the inner and outer sides of the steam heating pipe (200), and a driving assembly (500) corresponding to the stirring assembly (300) and the stirring and scraping assembly (400) is provided on the top of the reactor (100), wherein the driving assembly (500) comprises a gear box (510) supported on the top cover surface of the reactor (100), and the gear box (510) is provided with a gear box (510) inside thereof. The inner shaft (501) and the rotating drum (502) are assembled with a bearing insert, and the inner shaft (501) is assembled inside the rotating drum (502) through the bearing insert, the top of the inner shaft (501) is connected to a reducer (520) through a coupling, and the output end of the reducer (520) is connected to a motor (530), the reducer (520) and the motor (530) are both supported and assembled above the gear box (510), and the inner shaft (501) and the rotating drum (502) are assembled in the center of the top cover of the reactor (100) through the bearing insert and extend inside the reactor (100).

6. A method and device for recovering waste methanol purified by atmospheric distillation according to claim 5, characterized in that: The steam heating pipe (200) is arranged in a spiral shape, and a steam inlet pipe (210) and a steam outlet pipe (220) are integrally fixedly provided at the left and right ends of the steam heating pipe (200), respectively, and the steam inlet pipe (210) and the steam outlet pipe (220) are inserted and assembled on the left and right side walls of the upper part of the reaction kettle (100) through sealing flanges.

7. A method and device for recovering waste methanol by atmospheric distillation purification according to claim 6, characterized in that: The stirring assembly (300) comprises an inner stirring rod (310) and an outer stirring rod (320) which are vertically parallel to each other, and an upper beam (301) is fixedly arranged horizontally on the upper ends of the inner stirring rod (310) and the outer stirring rod (320), and the middle part of the upper beam (301) is mounted on the lower part of the outer wall of the rotating drum (502); the stirring and scraping assembly (400) comprises an inner scraping rod (410), a middle scraping rod (420) and an outer scraping rod (430) which are vertically parallel to each other, and the upper end of the inner scraping rod (410) is supported and mounted on the outer wall of the lower end of the inner shaft (501), and the inner scraping rod (410) and the scraping rod (430) are mounted on the lower part of the inner shaft (501). A lower beam (401) is fixedly arranged horizontally at the bottom ends of the middle rod (420) and the outer scraper rod (430); the outer side of the outer scraper rod (430) is attached to the inner wall of the reaction kettle (100); the steam heating pipe (200) is spirally wound between the outer scraper rod (430) and the outer mixing rod (320); and the upper end of the outer scraper rod (430) is lower than the bottom wall of the steam inlet pipe (210) and the steam outlet pipe (220); the middle scraper rod (420) is located between the inner mixing rod (310) and the outer mixing rod (320); and the inner scraper rod (410) is located on the inner side of the inner mixing rod (310).

8. A method and device for recovering waste methanol by atmospheric distillation purification according to claim 7, characterized in that: An upper ring (421) is fixedly disposed horizontally on the upper end of the middle scraper rod (420), and the upper ring (421) is lower than the upper beam (301); corresponding lower rings (311) are fixedly disposed on the lower ends of the inner mixing rod (310) and the outer mixing rod (320), and the lower rings (311) are higher than the lower beam (401); a corresponding bottom scraper rod (440) is fixedly disposed on the lower end of the outer scraper rod (430), and the bottom scraper rod (440) is arranged in an arc shape, and a support rib (441) is supported on the surface of the bottom scraper rod (440), and the upper end of the support rib (441) is supported and fixed to the lower beam (401).

9. The method and device for recovering waste methanol by atmospheric distillation purification according to claim 5, characterized in that: The gear box (510) is provided with corresponding upper bevel teeth (511), side bevel teeth (512) and lower bevel teeth (513), and the side bevel teeth (512) are meshed at the lower side of the upper bevel teeth (511), and the upper side of the lower bevel teeth (513) is meshed with the lower side of the side bevel teeth (512). The side bevel teeth (512) are assembled on the side wall of the gear box (510) through shafts and bearings, the upper bevel teeth (511) are fixed on the upper end of the inner shaft (501), and the side bevel teeth (512) are fixed on the outer wall of the upper end of the rotating drum (502).

10. A method and device for recovering waste methanol purified by atmospheric distillation according to claim 4, characterized in that: The reactor (100) is arranged in four equal parts, and the adjacent sides of the four equal parts of the reactor (100) are filled with sealing gaskets and assembled by bolt insertion, and the bottom of the sides of the reactor (100) and the bottom bin (103) are supported by a support frame (104), the outer wall of the reactor (100) is wrapped with thermal insulation cotton (105), and the thermal insulation cotton (105) is supported by an arm (106) on the outside, and the arm (106) is assembled on the outer wall of the reactor (100) by bolts.

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